Browser
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| posted on 22/10/08 at 09:25 AM |
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Cabin boom/buffet in modern cars
I don't know whether it's only me and Mrs Browser who have a problem with this, but our last two cars both seem to have suffered with this
problem. Seemingly at any speed much above 25mph, if anyone opens just one window the low-frequency noise generated in the cars passenger cabin is
very noticeable and, in our current car (a 2000 Cintroen Xsara Picasso) is actually uncomfortable if experienced for more than a few seconds. Cracking
open another window, preferably a front one, kills the problem, so I can only assume it is caused (with one window open) by air trying to get into the
car creating slighty higher pressure than ambient within the cabin, which then causes the air to reverse direction until the cabin pressure falls
below ambient at which point it reverses itself again, creating oscillating pressure and therefore sound waves.
As said before, the first car we noticed it on was the Toyota Carina we owned eight years ago, but I recently drove a new Vauxhall Astra hire car, and
the buffet-induced noise in that was so bad it felt like someone slapping the sides of your head!
Anyone else noticed this problem, or is it just us
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nitram38
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| posted on 22/10/08 at 09:32 AM |
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You're not driving fast enough! 
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Richard Quinn
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| posted on 22/10/08 at 09:34 AM |
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Mine does it with either or both of the rear windows down. I don't really consider it to be a problem with the climate in this bloody country!!
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speedyxjs
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| posted on 22/10/08 at 09:49 AM |
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I think it happens on your your current car because it is french
[Edited on 22-10-08 by speedyxjs]
How long can i resist the temptation to drop a V8 in?
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dan__wright
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| posted on 22/10/08 at 10:20 AM |
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havent been in a car that sodes this in a long time (think my dads on pug 405 did it about 12 years ago)
FREE THE ROADSTER ONE…!!
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smart51
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| posted on 22/10/08 at 10:43 AM |
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My wife's C3 does it if one of the front windows is open by just a small amount. If the window is half open or both front windows are open a
bit then it is fine.
Turbulent air flow over the opening causes the air in the car to resonate. Its like blowing over a bottle.
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whitestu
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| posted on 22/10/08 at 10:43 AM |
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Most cars I've had do this. My last Passat was terrible!
I thought all cars did it.
Stu
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Peteff
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| posted on 22/10/08 at 10:49 AM |
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It's got to do it with only one window open, the pressure drops inside as air is sucked out with nowhere for it to come back in till you open
another window and it equalises. Shut the windows and put the air con on
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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Rob Bartley
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| posted on 22/10/08 at 11:01 AM |
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Yep! Get that trouble all the time with most cars. We (as in me & my lovely wife) have nick named it "Helicopters"
I WILL get out again!!
I have a little bit......need more......
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Fred W B
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| posted on 22/10/08 at 11:09 AM |
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I get it too.
Didn’t Mythbusters do an episode once where they provided it was more efficient fuel wise to run with the aircon on, rather than with the window
open?
Regards
Fred W b
You can do it quickly. You can do it cheap. You can do it right. – Pick any two.
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I love speed :-P
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| posted on 22/10/08 at 11:15 AM |
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quote:
Originally posted by Fred W B
Didn’t Mythbusters do an episode once where they provided it was more efficient fuel wise to run with the aircon on, rather than with the window
open?
Regards
Fred W b
Not quite, if your going slow ish then its better to have the window open, if your going fast ish then its better to have the air con on. There is a
crossover speed where it doesn't matter which one you use but it all depends on the car in question.
i.e. at 30 its probably better to have the window open but at 50/60 better to have the air con on)
Don't Steal
The Government doesn’t like the competition
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Mr Whippy
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| posted on 22/10/08 at 12:07 PM |
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even my cortina did this, you need out more
Fame is when your old car is plastered all over the internet
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lotusmadandy
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| posted on 22/10/08 at 12:21 PM |
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Yup my vauxhall zafira does this with a rear window open slightly.
Andy
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02GF74
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| posted on 22/10/08 at 12:43 PM |
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not just you, this low frequency is very disturbing - the US used or investigated using it as a weapon in Viet-Nam war.
I first came across this in a jag (not mine) about 20 yrs ago - it happened when the sunroof was openened - jag then put an intermediate stop poisiton
for the sunroof to prevent it reaching that posiiton.
to over come this, you owuld need to open different windows or same windows different amounts to "tune" out the problem.
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nick205
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| posted on 22/10/08 at 02:55 PM |
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.......fascinating
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DarrenW
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| posted on 23/10/08 at 09:14 AM |
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Its happened to me on several cars. Not pleasant at all.
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David Jenkins
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| posted on 23/10/08 at 11:26 AM |
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I have the same 'problem' with my Yaris, and I solve it the same way as most people here - I open the opposite window a gnat's and
the oscillation stops.
Mind you - I wouldn't want to do it with manual windows - faffing around reaching across the front seat while motoring along is NOT a good idea!
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Rob Palin
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| posted on 29/10/08 at 01:11 PM |
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I've had to try and minimise this problem on several cars as part of work. Unfortunately it's damn-near impossible without seriously
compromising things other people just don't want compromising (including aero people themselves!).
You can treat it more effectively on sunrooves than side windows because you're given more lee-way. Check out the various little deflectors and
vortex generators (sometimes looking like mini castle battlements) that pop-up when you open a typical sunroof. That's what all those are there
for.
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